Display cabinets of such type typically have an elongated hollow configuration within which the food products are contained and a window panel extending forwardly and downwardly from a top of the cabinet for enclosing the front of the cabinet while permitting viewing of refrigerated food products and the like within the cabinet by passing customers. It is known to clamp the upper peripheral edge of the window panel in hinge assemblies and to utilize fluid controlled cylinders to facilitate pivotal movement of the window panel between a lowered, closed position and an upwardly raised, open position that permits access to the interior of the cabinet from the customer side in order to facilitate refilling of the cabinet with goods and cleaning of the cabinet interior.
Because thermal efficiency and energy costs are important considerations in operating commercial refrigeration units, it is desirable that the window panel in such display cabinets comprise a thermally insulated glass unit made up of two or more glass panes that are supported in spaced apart relation with the interior between the panes appropriately sealed. Since such thermal insulated glass units are relatively heavy due to the multiple glass pane construction, it has been difficult to lift such insulated window panels about an upper peripheral, horizontal pivot axis without crushing the edge of the glass unit that is clamped in the hinge assembly or otherwise damaging the glass unit. The relatively massive hinges required for supporting the window panel also can detract from the esthetic appearance of the cabinet, particularly when the window panel is in a raised position. The use of mounting screws to enhance securement of the thermal glass unit within the clamps of the hinge assemblies also can destroy the seal to the air insulating space between the glass panes, both adversely affecting the thermal efficiency of the glass unit as well as permitting moisture and other contaminants to migrate into the insulating space between the panes which can further detract from the appearance of the panel. As a result, it usually has been the practice to utilize single glass pane window panels in such display cabinets notwithstanding their thermal inefficiency. On the other hand, when thermal efficiency considerations dictate the use of insulated glass units, it has been necessary to support the glass unit for pivotal movement about a pivot axis adjacent the bottom of the glass unit, which can restrict design alternatives for the display cabinet and impede access to the cabinet.